Visitor design pattern
E679870
The Visitor design pattern is a behavioral software design pattern that lets you separate algorithms from the object structures they operate on, enabling new operations to be added without modifying the existing classes.
All labels observed (5)
| Label | Occurrences |
|---|---|
| Visitor pattern | 6 |
| Visitor design pattern canonical | 3 |
| Double dispatch | 1 |
| Gamma et al. (Gang of Four) Visitor pattern description | 1 |
| Gang of Four Visitor pattern | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T7665381 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Visitor design pattern Context triple: [Composite, relatedTo, Visitor design pattern]
-
A.
Template Method
Template Method is a behavioral design pattern that defines the skeleton of an algorithm in a base class while allowing subclasses to override specific steps without changing the algorithm’s overall structure.
-
B.
Chain of Responsibility
Chain of Responsibility is a behavioral design pattern that decouples senders and receivers by passing a request along a chain of potential handlers until one of them processes it.
-
C.
Design Patterns: Elements of Reusable Object-Oriented Software
Design Patterns: Elements of Reusable Object-Oriented Software is a seminal software engineering book by the "Gang of Four" that catalogues foundational object-oriented design patterns widely used in software development.
-
D.
Structural Pattern Matching
Structural Pattern Matching is a Python language feature, introduced via PEP 622, that enables powerful, declarative matching of complex data structures using a `match`/`case` syntax.
-
E.
Abstract Factory
Abstract Factory is a creational design pattern that provides an interface for creating families of related or dependent objects without specifying their concrete classes.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Visitor design pattern Target entity description: The Visitor design pattern is a behavioral software design pattern that lets you separate algorithms from the object structures they operate on, enabling new operations to be added without modifying the existing classes.
-
A.
Template Method
Template Method is a behavioral design pattern that defines the skeleton of an algorithm in a base class while allowing subclasses to override specific steps without changing the algorithm’s overall structure.
-
B.
Chain of Responsibility
Chain of Responsibility is a behavioral design pattern that decouples senders and receivers by passing a request along a chain of potential handlers until one of them processes it.
-
C.
Design Patterns: Elements of Reusable Object-Oriented Software
Design Patterns: Elements of Reusable Object-Oriented Software is a seminal software engineering book by the "Gang of Four" that catalogues foundational object-oriented design patterns widely used in software development.
-
D.
Structural Pattern Matching
Structural Pattern Matching is a Python language feature, introduced via PEP 622, that enables powerful, declarative matching of complex data structures using a `match`/`case` syntax.
-
E.
Abstract Factory
Abstract Factory is a creational design pattern that provides an interface for creating families of related or dependent objects without specifying their concrete classes.
- F. None of above. chosen
Statements (53)
| Predicate | Object |
|---|---|
| instanceOf |
behavioral design pattern
ⓘ
software design pattern ⓘ |
| applicableWhen |
classes defining the object structure rarely change
ⓘ
many unrelated operations need to be performed on objects in a structure ⓘ object structure is relatively stable ⓘ |
| belongsTo |
Gang of Four design patterns
ⓘ
linked to:
Gang of Four design pattern
|
| benefit |
can simplify maintenance of complex operations
ⓘ
facilitates adding cross-cutting operations ⓘ improves separation of concerns between data structures and operations ⓘ keeps related operations together in visitor classes ⓘ supports accumulation of state during traversal ⓘ |
| commonUseCase |
code analysis tools
ⓘ
compilers and abstract syntax tree processing ⓘ document object model traversal ⓘ operations on hierarchical data structures ⓘ |
| coreMechanism | double dispatch ⓘ |
| definesCollaborationBetween |
Element
ⓘ
ObjectStructure ⓘ Visitor ⓘ |
| describedIn | Design Patterns: Elements of Reusable Object-Oriented Software ⓘ |
| drawback |
adding a new element class requires changes to all existing visitors
ⓘ
can break encapsulation by exposing element internals to visitors ⓘ increases coupling between visitors and element classes ⓘ |
| enables | adding new operations by creating new visitor classes ⓘ |
| hasAlias | Visitor ⓘ |
| hasCategory | behavioral pattern ⓘ |
| introducedBy |
Erich Gamma
ⓘ
John Vlissides ⓘ Ralph Johnson ⓘ Richard Helm ⓘ |
| keyMethod |
accept()
ⓘ
visit() ⓘ |
| oftenUsedWith |
composite pattern
ⓘ
interpreter pattern ⓘ
linked to:
Interpreter
iterator pattern ⓘ |
| primaryIntent |
enable adding new operations without modifying existing classes
ⓘ
separate algorithms from object structures ⓘ |
| relatedConcept |
double dispatch
ⓘ
open/closed principle ⓘ
linked to:
Open-Closed Principle
separation of concerns ⓘ |
| requires | modifying visitor interface when adding new element types ⓘ |
| supports | open/closed principle ⓘ |
| supportsLanguageFeature | emulation of multiple dispatch in single-dispatch languages ⓘ |
| tradeOff | easy to add new operations but hard to add new element classes ⓘ |
| typicalLanguageContext | object-oriented programming ⓘ |
| typicalStructureElement |
ConcreteElement class
ⓘ
ConcreteVisitor class ⓘ
linked to:
ConcreteVisitor
Element interface ⓘ ObjectStructure class ⓘ Visitor interface ⓘ |
| usedFor |
defining new operations on object structures
ⓘ
performing operations on elements of an object structure ⓘ traversing complex object structures ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Visitor design pattern Description of subject: The Visitor design pattern is a behavioral software design pattern that lets you separate algorithms from the object structures they operate on, enabling new operations to be added without modifying the existing classes.
Referenced by (12)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern
linked to: Visitor design pattern